首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 480 毫秒
1.
OBJECTIVES: To determine whether pharmacological induction of heat shock proteins (HSPs) by herbimycin-A (a tyrosine-kinase inhibitor) would protect against neutrophil-mediated lung injury in an animal model of lower torso ischaemia-reperfusion. MATERIALS AND METHODS: Sprague-Dawley rats were randomised into three groups: the control group underwent midline laparotomy only; the ischaemia-reperfusion (IR) group underwent laparotomy and clamping of the infrarenal abdominal aorta for 30 min followed by 2 h of reperfusion; the third group (HerbIR) was pretreated with herbimycin-A 18 h prior to IR insult. Wet to dry lung weight ratio (W:D), bronchoalveolar lavage protein concentration (BALprot), tissue myeloperoxidase activity (MPO) and bronchoalveolar lavage neutrophil count (BALPMN) were measured. Heat shock protein 72 (HSP72) expression in lung, intestine, mesentery and liver was measured using Western immunoblotting. RESULTS: IR resulted in acute lung injury with tissue oedema (W:D) and neutrophil infiltration (PMO, BALPMN). Herbimycin-A, in vivo, induced HSP expression and attenuated neutrophil infiltration (MPO, BALPMN). CONCLUSION: These data indicate that herbimycin-A protects against ischaemia-reperfusion induced pulmonary neutrophil infiltration, possibly by increasing the expression of heat shock proteins.  相似文献   

2.
BACKGROUND: Granulocyte colony-stimulating factor (G-CSF) increases production and release of neutrophil precursors and activates multiple functions of circulating polymorphonuclear neutrophils (PMNs). G-CSF has therapeutic effects in many experimental models of sepsis; its actions with superimposed reperfusion insults are unknown. In traumatic conditions, G-CSF could exacerbate unregulated, PMN-dependent injury to otherwise normal host tissue or, it could partially reverse trauma-induced immune suppression, which may improve long-term outcome. This study tested whether stimulating PMN proliferation and function with G-CSF during recovery from trauma+sepsis potentiated reperfusion injury or whether it improved host defense. METHODS: Anesthetized swine were subjected to cecal ligation and incision, 35% hemorrhage, and 1 hr of hypotension. Resuscitation consisted of intravenous G-CSF (5 microg/kg) or placebo followed by shed blood and 40 mL/kg of lactated Ringer's solution. The control group received laparotomy only. G-CSF or placebo was given daily. Animals were killed at 4 days. Observers, blind to the protocol, graded autopsy samples for localization of infection and quality of abscess wall formation. Data included complete blood count, granulocyte oxidative burst after phorbol myristate acetate stimulation in vitro (GO2B), bronchoalveolar lavage (BAL) cell count, BAL noncellular protein, lipopolysaccharide-stimulated tumor necrosis factor production in whole blood in vitro (lipopolysaccharide-tumor necrosis factor), and lung tissue myeloperoxidase (MPO). RESULTS: Neutrophilia and localization of infection, were significantly improved by G-CSF. Variables altered by G-CSF, though not significantly, showed GO2B potential increased by 50%, lipopolysaccharide-tumor necrosis factor decreased by 50%, and improved survival versus placebo (100% vs. 70%). G-CSF did not increase lung MPO, BAL cell count, or BAL protein. Both arterial and venous O2 saturations were unaltered. CONCLUSIONS: Our data show that G-CSF initiated at the time of resuscitation reduced the sequelae of posttrauma sepsis by increasing PMN proliferation and function without potentiating PMN-mediated lung reperfusion injury.  相似文献   

3.
The effects of bacterial endotoxin (lipopolysaccharide, LPS) are amplified by lipopolysaccharide binding protein (LBP) and CD14, resulting in cellular activation at very low concentrations of LPS. To investigate the importance of this pathway in acute lung injury, we measured LPS, LBP, and soluble CD14 (sCD14) in the bronchoalveolar lavage fluid (BAL) of 82 patients with acute respiratory distress syndrome (ARDS). LBP and sCD14 increased markedly in BAL of patients with ARDS. sCD14 and LBP each were strongly related to BAL total protein and polymorphonuclear neutrophil (PMN) concentration, whereas LPS concentration was not. Multivariate analyses showed sCD14 to be strongly related to BAL total protein, even after controlling for LPS and LBP concentrations. sCD14 was strongly and independently related to PMN concentration, after controlling for BAL LPS, LBP, and interleukin-8 (IL-8). The BAL LPS concentration was not strongly related to either BAL total protein or BAL PMN. The BAL sCD14 and LBP values were similar in all subgroups of patients with ARDS, and were not related to survival. The serum LBP and sCD14 were elevated in ARDS, but were not related to BAL total protein, LBP, sCD14, PMN, or clinical outcome. Thus, LBP and sCD14 reach high concentrations in the lungs of patients with ARDS, and BAL sCD14 is strongly related to two major indices of lung inflammation: total protein and PMN concentration. CD14-dependent mechanisms may contribute to lung inflammation in ARDS.  相似文献   

4.
Morphology of the lungs and bronchoalveolar lavage (BAL) were studied in 27 patients with tuberculomas. The investigators also determined lymphocytic, macrophagal or neutrophil BAL composition regarding lymphocyte, macrophage or neutrophil dominating infiltration of pulmonary tissue outside the sites of specific inflammation. As a result, the activity of the process was assessed by subpopulation composition of lymphocytes in BAL, by morphology of alveolar macrophages in pulmonary tissue; the pattern of inflammatory reaction in the lesion focus was specified.  相似文献   

5.
By using the model of acute injury caused by intrapulmonary deposition of IgG immune complexes, blocking mAb to CD11a, CD11b, L-selectin, and intercellular adhesion molecule-1 (ICAM-1) were administered either i.v. or intratracheally (i.t.). The effects of these interventions were assessed according to lung injury, lung content of myeloperoxidase (MPO), TNF-alpha, and cellular content in bronchoalveolar lavage (BAL) fluids, and up-regulation of pulmonary vascular ICAM-1. In animals treated i.v. with Abs to CD11a, L-selectin, or ICAM-1 lung injury was significantly attenuated in parallel with reduced lung content of MPO. Under similar conditions, treatment with anti-CD11b had no effect. However, when the same mAb were administered i.t., anti-CD11a and anti-L-selectin were without protective effects, whereas i.t. administered anti-CD11b and anti-ICAM-1 were each highly protective. The protective effects of anti-CD11b were related to profound reductions in BAL levels of TNF-alpha, pulmonary vascular up-regulation of ICAM-1, and lung content of MPO. The protective effects of i.t.-administered anti-ICAM-1 were not associated with reduced BAL levels of TNF-alpha. Protective effects of mAb were also reflected in reductions of retrievable neutrophils in BAL fluids. mAb to rat CD11b and CD18 but not to rat CD11a suppressed in vitro production of TNF-alpha by immune complex-stimulated rat alveolar macrophages. The mAb did not reduce NO2-/NO3- generation in stimulated macrophages but all mAb (except anti-ICAM-1) reduced O2- responses in macrophages. These data suggest a compartmentalized role for adhesion molecules in lung inflammatory injury after intraalveolar deposition of IgG immune complexes, with CD11a, L-selectin, and ICAM-1 being important in the vascular compartment for neutrophil recruitment, whereas in the alveolar compartment CD11b and ICAM-1 (but not CD11a and L-selectin) seem to play key roles.  相似文献   

6.
Macrophage migration inhibitory factor (MIF) is a recently rediscovered pro-inflammatory cytokine that has the unique potential to override the anti-inflammatory action of glucocorticoids. Since recent reports suggest the pivotal role of MIF in acute lung injury, we examined the protective effect of anti-MIF antibody on lipopolysaccharide (LPS)-induced acute lung injury in rats. Rats were injected with LPS (7 mg/kg) intraperitoneally with or without pretreatment with anti-MIF antibody. The anti-MIF antibody significantly attenuated LPS-induced migration of neutrophils to the lungs at 4 and 24 h as demonstrated by observation of the number of neutrophils per alveolus, the activity of myeloperoxidase of the lung tissue, and cell differentiation of neutrophils in bronchoalveolar lavage (BAL) fluid. The increased level of macrophage inflammatory protein-2, a powerful neutrophil chemokine, in BAL fluid was also significantly attenuated by pretreatment with the anti-MIF antibody as compared with the control group. Additionally, positive immunostaining for MIF was observed in bronchial epithelial cells and alveolar macrophages, and Northern blot analysis of lung tissues demonstrated increased MIF mRNA 24 h after LPS injection. These data suggest that the anti-MIF antibody has therapeutic potential for the treatment of acute lung injury by suppressing the level of neutrophil chemokine in the lungs.  相似文献   

7.
OBJECTIVE: To assess the effects of the lazaroid, tirilazad mesylate, a potent lipid peroxidation inhibitor, in an animal model of Pseudomonas sepsis. DESIGN: Comparison of four experimental groups: a) saline control; b) Pseudomonas sepsis control; c) tirilazad mesylate control; and d) sepsis with tirilazad mesylate pre treatment. SETTING: University animal laboratory. SUBJECTS: Hanford minipigs (20 to 25 kg), anesthetized with pentobarbital and mechanically ventilated on an FIO2 of 0.4. INTERVENTIONS: Sepsis was induced by infusing Pseudomonas aeruginosa at 1 x 10(6) colony-forming units/kg/min over 120 mins. The tirilazad mesylate-treated group received a 5-mg/kg bolus 30 mins before, and a 3-mg/kg bolus 3 hrs after, the onset of sepsis. Hemodynamics, PaO2, and neutrophil counts were measured for 6 hrs. Thiobarbituric acid reactive material (TBARM) in tissue (lung, liver, and intestine), lung wet/dry weight ratio, lung myeloperoxidase activity, plasma tumor necrosis factor (TNF)-alpha concentrations, protein content, and percent neutrophils in bronchoalveolar lavage fluid were evaluated at the time the animals were killed (6 hrs). MEASUREMENTS AND MAIN RESULTS: Sepsis induced significant systemic hypotension, pulmonary hypertension, hypoxemia, and neutropenia. Sepsis also significantly increased TBARM content, lung wet/dry weight ratio, myeloperoxidase activity, plasma TNF-alpha concentrations, and bronchoalveolar lavage neutrophil percentage. Treatment with tirilazad mesylate significantly attenuated hypoxemia and decreased TBARM content, lung wet/dry weight ratio, myeloperoxidase activity, bronchoalveolar lavage protein, and bronchoalveolar lavage neutrophil percentage, but did not affect sepsis-induced hemodynamics, including systemic hypotension and pulmonary hypertension, plasma TNF-alpha concentrations, or neutropenia. CONCLUSIONS: Pretreatment with the tirilazad mesylate did not change P. aeruginosa sepsis-induced hemodynamic consequences. However, tirilazad mesylate attenuated sepsis-induced acute lung injury.  相似文献   

8.
STUDY OBJECTIVE: To investigate the pathogenesis of lung injury in Pneumocystic carinii pneumonia and nonspecific interstitial pneumonitis (NIP), common pulmonary complications of human immunodeficiency virus (HIV) infection. The efficacy of corticosteroid therapy in P carinii pneumonia and the observation that bronchoalveolar lavage (BAL) neutrophilia predicts a poor prognosis support the premise that the lung injury of P carinii pneumonia is due to the host's inflammatory response to the infection. DESIGN: In vitro measurements on previously collected BAL fluid samples. SETTING: The Clinical Center of the National Institutes of Health, a research hospital and tertiary care referral center. PATIENTS: Five normal volunteers, 5 asymptomatic HIV-positive patients, 10 HIV-positive patients with NIP (5 asymptomatic and 5 with respiratory symptoms), and 19 HIV-positive patients with P carinii pneumonia. MEASUREMENTS AND RESULTS: BAL leukotriene B4 (LTB4), interleukin 8 (IL-8), and phospholipase A2 (PLA2) were measured. IL-8 and PLA2 were elevated in patients with P carinii pneumonia, and IL-8 correlated with BAL fluid absolute neutrophil count. LTB4, IL-8, and PLA2 levels were elevated in patients with NIP; LTB4 and PLA2 levels correlated with absolute neutrophil count, and IL-8 correlated with alveolar-arterial oxygen pressure difference. IL-8 was elevated in the asymptomatic HIV-positive patients, and there was a trend toward elevation of PLA2 in this group. CONCLUSION: IL-8 appears to play a role in the pathogenesis of lung injury in P carinii pneumonia and may be the principal neutrophil chemotaxin in this disease; PLA2 may also be involved in the pathogenesis of P carinii pneumonia. Both LTB4 and IL-8 may be involved in the recruitment of neutrophils and subsequent lung injury of NIP. These data suggest that there are varying mechanisms by which inflammatory cells are recruited to the lung in different HIV-related lung diseases.  相似文献   

9.
There is ample experimental evidence that polymorphonuclear neutrophils (PMN) play a critical role in the pathogenesis of the adult respiratory distress syndrome (ARDS). Since interleukin-8 (IL-8) is a strong chemotactic factor for PMN, we measured IL-8 levels in plasma and bronchoalveolar lavage (BAL) fluid of 18 patients, 12 with ARDS and 6 with severe pneumonia uncomplicated by ARDS, all of whom had an increased number of PMN in BAL fluid. Seven healthy subjects served as controls. We found elevated levels of IL-8 in the alveolar spaces of all patients tested. Elevated BAL IL-8 levels were related to a fatal outcome and the presence of shock and correlated with a general clinical severity index (simplified acute physiological score). BAL fluid levels of IL-8 were significantly higher in patients with ARDS than in patients with pneumonia. In plasma, IL-8 levels were increased similarly in all patients and did not correlate with survival or the presence of shock. The BAL fluid-to-plasma ratio of IL-8 was significantly greater than that of tumor necrosis factor alpha, indicating higher local production of IL-8. Moreover, the presence of a primed subpopulation of blood PMN with respect to H2O2 production indicates that IL-8 may contribute to the neutrophil-mediated process in the pathogenesis of ARDS and pneumonia.  相似文献   

10.
Expression of mRNA for the neutrophil (PMN) chemokine, KC, in rat models of lung injury suggests a role for this chemokine in pulmonary inflammation. We addressed this hypothesis at the protein level by functionally characterizing recombinant rat KC (rKC) in vitro and in vivo. In vitro, rKC induced PMN chemotaxis and increased the expression of CD11b/CD18 on PMNs. Recombinant KC also induced a respiratory burst (quantitated by flow cytometry) in rat PMNs, similar to that caused by its human structural homologue, gro/melanoma growth-stimulating activity, on human PMNs, but less than that caused by IL-8 on human PMNs. Intratracheal instillation of rKC induced dose-dependent PMN influx into airspaces (average PMNs in bronchoalveolar lavage: vehicle = 1.5%, n = 4; rKC (1 microgram) = 11.5%, n = 2; rKC (10 micrograms) = 77.3%, n = 2). A neutralizing anti-KC Ab reduced the chemotactic activity of rat bronchoalveolar lavage fluid collected after the intratracheal administration of LPS (48.3 +/- 8% of control, n = 4). Anti-KC neutralizing Ab markedly inhibited PMN accumulation (71 +/- 6%) within the lungs in response to an intratracheal challenge of LPS. We conclude that rat KC is a major but not exclusive mediator of PMN activation and recruitment during LPS-induced pulmonary inflammation.  相似文献   

11.
The neuropeptide gastrin releasing peptide (GRP) is present in the lung, and functions as a modulator of tissue growth and repair in fibrotic processes, or as a modulator of cell movement and differentiation in various inflammatory processes, including granulomatous ones. In idiopathic pulmonary fibrosis (IPF), changes in the bronchoalveolar lavage (BAL) content of GRP can be expected. We measured GRP-like immunoreactive substances (GRP-IS) and another neuropeptide, vasoactive intestinal peptide (VIP)-IS in BAL by enzyme immunoassay. Our results showed a decrease in BAL GRP-IS in patients with IPF (26.5 +/- 5.5 pg.mg-1 protein) and sarcoidosis (35.9 +/- 9.2 pg.mg-1), compared to healthy nonsmokers (63.4 +/- 9.0 pg.mg-1). When data were expressed as pg.ml-1 BAL fluid recovered, a decrease was only seen in IPF, not in sarcoidosis. The levels of VIP-IS in BAL were not different between the groups studied. Increased protein levels in BAL had no correlation with the levels of GRP-IS or VIP-IS in BAL. Furthermore, BAL neutrophil percentages had no correlation with the levels of GRP-IS in BAL of patients with IPF. Using reversed phase high performance liquid chromatography (HPLC), several kinds of GRP-IS were detected in BAL. These findings suggest that the decreased level of GRP-IS in BAL may reflect a loss of GRP-producing cells due to chronic lung injury and fibrosis in patients with IPF.  相似文献   

12.
1. Tumour necrosis factor-alpha (TNF-alpha) is a cytokine with diverse properties consistent with a possible role in inflammatory disease. We investigated whether TNF-alpha is induced during the progression of lung inflammation elicited by a particulate non-antigenic stimulus, and whether pharmacological control of TNF-alpha expression influences recruitment of specific inflammatory cell types. 2. A single intravenous injection of Sephadex particles into rats led to extensive granulomatous inflammation in lung alveolar and bronchial tissue that peaked in intensity after 24-72 h. Mononuclear cells were the principal component of granulomas, but neutrophils and eosinophils were also abundant. Numbers of mononuclear cells, neutrophils and eosinophils recovered by bronchoalveolar lavage (BAL) peaked at 72 h, 48 h and 72 h, respectively. 3. Messenger RNA encoding TNF-alpha was induced in lung epithelial cells, lung granulomas and BAL cells 6 h after Sephadex administration and remained elevated for 72 h before declining to baseline by 7 days. In BAL cell populations TNF-alpha protein was localized to mononuclear cells at all times points pre- and post-Sephadex administration. 4. Treatment of rats with dexamethasone significantly reduced the Sephadex-induced recruitment of mononuclear cells, neutrophils and eosinophils into the bronchoalveolar cavity, and significantly reduced TNF-alpha mRNA expression by BAL cells. 5. Treatment of rats with cyclosporin A was without effect on Sephadex-induced elevations of mononuclear cell numbers and expression of TNF-alpha, but did reduce significantly recruitment of neutrophils and eosinophils to BAL cell populations. 6. These results show that a sequential asthma-like recruitment of neutrophils, eosinophils and mononuclear cells into lung tissue can be induced by single exposure to a non-antigenic stimulus. Pharmacological and histological studies reveal that mononuclear cell mobilization relates closely to induced TNF-alpha expression, whereas mobilization of neutrophils and eosinophils appears secondary to expression of the cytokine.  相似文献   

13.
Leukocyte emigration and alveolar macrophage-derived cytokines may contribute to lung microvascular injury associated with adult respiratory distress syndrome. We have used mAbs against cell adhesion molecules on leukocytes (anti-CD18 and anti-CD49d) or against IL-8 to investigate these contributions. Intratracheal (i.t.) instillation of LPS (50 microg/kg) caused a significant increase in bronchoalveolar lavage polymorphonuclear leukocytes (PMNs) without an increase in mononuclear cells (MNCs) or an increase in lung permeability. Injection of LPS (10 microg/kg) i.v. at 24 h after i.t. LPS caused significant increases in bronchoalveolar lavage PMNs, MNCs, IL-8, and monocyte chemotactic protein-1, as well as increases in lung permeability. Rabbits that were administered i.t. LPS followed by i.v. LPS and treated with anti-CD18 mAb had a significantly lower lung permeability index and emigration of fewer PMNs but no change in MNC emigration compared with saline treatment. Anti-IL-8 mAb treatment resulted in a significantly lower lung permeability index with no change in PMN emigration compared with no treatment. These results suggest that PMN emigration is necessary but not sufficient for the development of LPS-induced lung injury, and that IL-8 plays a significant role in PMN-dependent lung injury, independent of PMN emigration.  相似文献   

14.
Amelioration of liver injury by ischaemic preconditioning   总被引:1,自引:0,他引:1  
BACKGROUND: Ischaemic preconditioning, i.e. preparatory brief ischaemia before subsequent long ischaemia, can effectively protect the heart from ischaemia-reperfusion injury in animals. The purpose of this study was to demonstrate the same phenomenon in the liver. METHODS: Using warm ischaemia-reperfusion of 70 per cent of the liver followed by resection of the non-ischaemic portion in rats, livers with 10 min of ischaemic preconditioning, i.e. 10 min of warm ischaemia and reperfusion, were compared with those that had not been subjected to such a manoeuvre. RESULTS: At 120 min after reperfusion following 40 min of warm ischaemia, the livers with 10 min of ischaemic preconditioning had a significantly lower mean(s.d.) serum alanine aminotransferase level (492(217) versus 1236(695) units/l; P < 0005) and lactic dehydrogenase level (7905(4002) versus 15066(9201) units/l; P< 0.05), as well as a higher bile output (0.12(0.03) versus 0.09(0.04) ml per g liver; P < 0.05) and liver tissue adenosine 5'-triphosphate level (78(13) versus 61(11) per cent; P< 0.05) than the control livers. The necrosis rate, histologically defined as the percentage of necrotic area in given liver sections, was reduced significantly by this manoeuvre (mean(s.d.) 1.3(1.3) versus 5.3(1.7) per cent; P< 0.05). CONCLUSION: Ischaemic preconditioning exerts a protective effect on hepatic warm ischaemia-reperfusion injury. Such a manoeuvre may be useful for hepatic resection in the clinical setting.  相似文献   

15.
Acute lung injury (ALI) of rabbits was induced by endotoxin and the effects of Reduqing (RDQ) injection on the following indexes were studied. The results showed that the arterial blood pH, PCO2, lung/body index, lung wet/dry weight ratio, the protein and neutrophil contents in bronchoalveolar lavage fluid increased significently together with arterial PO2 marked drop, which were consistent with lung tissue damage, while administration of RDQ simultaneously ameliorated these changes. It is suggested that the Chinese herbal medicine RDQ injection could protect rabbit from the endotoxin-induced ALI.  相似文献   

16.
Pulmonary asbestos burdens are usually determined by quantitative pulmonary dust analysis. The aim of this study was to investigate the value of bronchoalveolar lavage (BAL) for this purpose. First, the upper limit of normal for asbestos bodies (AB) in BAL fluid was established using a reference group of 371 patients with no evidence of increased exposure to asbestos. 99% of these patients had less than 0.5 AB/ml. In order to see whether BAL fluid AB concentration reflected pulmonary tissue content, BAL fluid and lung tissue from a further 64 patients with diverse histories of asbestos exposure were investigated. There was a positive association between AB concentration in BAL fluid and lung tissue only for the overall group of 64 patients (r = 0.86; P < 0.001). Twelve of 13 patients with more than 1 AB/ml and ten patients with more than 5 AB/ml had more than 1000 AB/cm3 lung tissue, a value that is usually exceeded in asbestosis. When the upper concentration limit was set at 0.5 AB/ml for BAL fluid and 50 AB/cm3 for lung tissue, only two out of 64 patients had a false positive value (specificity 95%), but eleven patients had false negative results (sensitivity 58%). These investigations establish that concentrations of > or = 0.5 AB/ml are a reliable indicator of increased asbestos exposure and concentrations > 1 AB/ml are associated with a higher probability of having more than 1000 AB/cm3 lung tissue. However, exclusion of increased asbestos exposure is not possible on the basis of negative BAL findings, since the sensitivity of the method is too low.  相似文献   

17.
Large numbers of neutrophils with unopposed neutrophil elastase (NE) proteolytic activity are found in lower respiratory tract secretions from most patients with advanced cystic fibrosis (CF). To determine whether antielastase defenses may be overwhelmed in epithelial lining fluid after lung transplantation, we measured NE activity (cleavage of the specific substrate, MeO-Suc-Ala-Ala-Pro-Val-pNA) in bronchoalveolar lavage fluids (BALF) obtained for surveillance or diagnostic purposes at various intervals (1 mo to 7 yr after transplantation) from 52 recipients who had undergone double or bilateral lung transplantation for end-stage CF. Unopposed NE activity was found in BALF from 14 recipients, most of whom also had >= 10(5) colony forming units (cfu) of Pseudomonas aeruginosa in BALF. Ten of the 14 recipients with unopposed NE in bronchoalveolar lavage (BAL) had developed obliterative bronchiolitis (OB), but only 8 of the 38 subjects without unopposed NE activity had OB (p = 0. 002; Fisher exact test). We conclude that antiprotease defenses in lower respiratory tract secretions of CF patients receiving lung allografts are sufficient in the majority of patients to prevent unopposed NE activity. However, the presence of unopposed NE activity in BAL from lung allografts of patients with CF is associated with progressive, irreversible OB and graft failure.  相似文献   

18.
The induction of heat shock protein 72 (hsp72) has been described in various experimental models of brain injury. The present study examined hsp72 expression patterns within the rodent cerebral cortex in experimental paradigms designed to mimic two mechanisms of damage produced by penetration of the cerebral cortex: (1) tissue tearing from the missile track and (2) diffuse excitotoxicity during temporary cavitation and shock wave formation. Adult male Spaque-Dawley rats received controlled penetration (stab) or injection of the NMDA receptor excitotoxin, quinolinic acid (QA), into the frontal cortex and were killed 1-24 h later. Tissue from the lesioned, sham-operated, or contralateral uninjected cortex was processed for Western and immunocytochemical analyses of hsp72 protein expression. By 12 h, both controlled penetration and excitotoxic brain injuries produced significant increases in hsp72 immunoreactivity, which decreased toward control levels at 24 h. However, the severity and regional distribution of hsp72 expression varied between the two models. Specifically, the controlled penetration injury produced many hsp72-expressing cells near the needle track, while immunoreactive cells within the QA-injected cortex were found in the periphery of the lesion site. Morphological assessment of brain sections subjected to dual-labeling procedures demonstrated that cells expressing hsp72 were primarily neuronal in both models of injury. These results suggest that although controlled penetration and diffuse excitotoxicity may induce similar temporal and cellular patterns of hsp72 expression, the spatial location of hsp72-immunoreactive cells may differ between the two models.  相似文献   

19.
To assess the role of some pro-inflammatory cells in inflammatory processes in lung cancer by measuring their respective activation markers in different portions of bronchoalveolar lavage (BAL) fluid. Prospective study in a university hospital. We studied 52 BAL samples, 37 from patients with lung cancer and 15 from a control group, using a radioimmunoassay technique to analyze for tryptase (T), hyaluronic acid (HA) and eosinophil cationic protein (ECP) in separate bronchial and bronchoalveolar samples from BAL fluid. Statistical analysis was performed using the R-SIGMA program. Patients with tumors had significantly higher T and HA levels in BAL fluid than did control patients, in both bronchial and bronchoalveolar portions. Lung cancer patients had higher T and ECP levels in bronchoalveolar portions. Mast cells and fibroblasts, at least, play a part in lung cancer, mainly in the distal portions of the bronchial tree.  相似文献   

20.
It is well known that ozone (O3) causes acute lung inflammation. What is not known is whether there is progression of the inflammatory response in humans with repeated short-term exposures. Our study was designed to test the hypothesis that repeated exposures to a high-ambient concentration of O3 (0.2 ppm) over several days would cause more inflammation than a single exposure. Fifteen healthy volunteers were exposed in random fashion to 0.2 ppm ozone for 4 h on a single day and to 0.2 ppm O3 for 4 h on 4 consecutive days while exercising moderately for 30 min of each hour. Pulmonary function tests were obtained immediately before and after each 4-h exposure. Bronchoscopy was performed 20 h after the completion of each exposure arm to obtain bronchoalveolar lavage (BAL) for measurement of markers of inflammation. Our results show initial progression followed by attenuation of the acute physiologic response to O3 with repeated daily exposures. We found a significant difference in percent change in FEV1, FVC, and specific airway resistance (SRaw) across the single-day exposure when compared with the change across Day 4 of the 4-d exposure. Bronchial fraction (the first 15 ml of BAL return) and BAL were analyzed for the following end points: total and differential cell counts, total protein, lactate dehydrogenase (LDH), fibronectin, interleukin-6 (IL-6), interleukin-8 (IL-8), and granulocyte-macrophage colony-stimulating factor (GM-CSF). In the bronchial fraction the number of polymorphonuclear cells (PMN)s and fibronectin concentration were significantly decreased after 4-d exposure compared with single-day exposure. In BAL, significant decreases in the number of PMNs, fibronectin, and IL-6 were found after 4-d exposure versus single-day exposure. These results suggest that there is attenuation of the O3-induced inflammatory response in both proximal airways and distal lung with repeated daily exposures.  相似文献   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号